Electrolytic apparatus.



PATENTED MAY 10, 1904.

H. S. BLAG'KMORE. ELECTROLYTIC APPARATUS.

APPLICATION FILED FEB. 23, 1004.

N0 MODEL.

ix QUE w? unuw New. :ry Ma Zliatented May 10, 1904.

UNITED STATES PATENT OEEIcE.

HENRY SPENCER BLAOKMORE, OF MOUN" VERNON, NEW YORK.

ELECTROLYTIC APPARATUS- SPEGIFICATION forming part of Letters Patent No. 759,799, dated May 10, 1904.

Original application filed July 22, 1903, $e1'ial No. 166,566. Divided and this application filed February 23, 1904. Serial To all, whom it may concern:

Be it known that I, HENRY SPENCER BLACK- MORE, a citizen of the United States, residing at Mount Vernon, in the county of Westchester and State of New York, have invented new and useful Improvements in Electrolytic Apparatus, of which the following is a specification.

This apparatus is especially intended for the production of a lead-sodium alley or a mercury-sodium amalgam and the recovery of the sodium therefrom as hydrate or oXid, being a division from Serial No. 166,566, liled July 22, .1903.

Referring to the accompanying drawings, Figure 1 is a transverse vertical section of an apparatus employing a molten electrolyte and cathode. Fig. 2 is a transverse vertical section of an apparatus employing an aqueous solution of an electrolyte and a cathode of mercury, and Fig. 3 is a transverse vertical section of a modified apparatus.

The apparatus of Fig. 1 consists of the following parts: An iron vessel 1 is set within a furnace-casing 2, of lire-brick, and supported therein, in part, by an annular fiange 3,extending outwardly from the upper edge of the vessel and resting upon the fire-brick, and, in part, by pier 4, rising centrally from the bottom of the furnace-chamber into supporting contact with the bottom of the vessel. The contents of the vessel are brought into a molten condition by any suitable means, that shown being a burner 5, extending through an opening 6 in the side wall of the furnace. The electrolyte and cathode may be subsequently maintained in a molten condition by the electrolyZing-current. From the flange of the vessel a cathode-terminal 7 extends to a binding-post 8. The vessel has an iron cover 9, supported by, but insulated from, the vessel by an insulating-packing 10, preferably of magnesia. The cover has a side opening 11 with closure 12 to permit the introduction of lead and a large central opening 13, within which is arranged the anode chamber 14. This anode-chamber consists of a tubular casing 15, of iron, having an inwardly-extending flange 16 at its lower open end, a cover 17 (N0 model.)

with central opening for the anode-terminal, and a non-conducting lining 18, preferably of magnesia, which at the upper end of the chamber extends out between a flange at the upper end of the casing and a corresponding flange on the cover to provide an insulating-packing. The anode-chamber has a lateral neck 19 with tight-fitting cover 20 for the introduction of sodium chlorid or other material to be electrolyzed. The flange 16 at the lower end of the anode-chamber supports a disk 21, of foraminous material, preferably iron-wire gauze, which disk is overlaid by adiaphragm 22. This diaphragm preferably consists of loose granular material of greater specific gravity than the molten electrolyte and less specific gravity than the molten cathode arranged upon support 21in a layer of considerable depth. The material which I have found especially suitable for such diaphragm when molten sodium chlorid is to be electrolyzed is magnetite broken into angular fragments of such size as to pass through a sieve having a mesh of lifty to the inch. The molten lead 23, acting as a cathode, preferably rises to such a height in vessel 1 that the entire mass of loose material-22, constituting the diaphragm, floats upon the surface of the lead, the diaphragm thereby remaining in close contact with the cathode notwithstanding considerable change in the surface level of the molten lead. The wiregauze 21 is merelya safety device to prevent the material of the diaphragm from dropping out of the anode-chamber in case the molten lead falls to any abnormal low level and is not necessary to the proper working of the apparatus. The anode 24, which may be a rod or rods of graphitized carbon, is carried by an adjustable rod 25, which may be of metal protected with porcelain, and extends through a stuffing-box 26 in cover 17. From one side of the anode-chamber extends an outlet-pipe 27 to draw off ehlorin or other gaseous products, the removal of this chlorin being perfectly assisted by the action of an air-injector 28 in pipe 27, which serves to maintain a slight vacuum in the anode-charm ber. The lead-sodium alloy produced by electrolysis of the molten sodium chlorid being lighter than lead is continuously displaced as formed from the surface of the cathode beneath the diaphragm and rises to the surface of the cathode around the anode-chamber, this being at a higher level than below the diaphragm. The alloy may be thence drawn off. It is preferable, however, to continuously remove the sodium from the alloy and convert it into its hydrate or oxid, the remaining lead being returned by gravity to the bottomof vessell beneath the diaphragm to receive further additions of sodium. This result may be accomplished in various ways, but preferably by the following means: Within and some distance below the surface of the molten-lead cathode is an annular pipe 29, arranged around and concentric with the anode-chamber. This pipe has two rows of downwardly and outwardly opening perforations 30. Connecting with pipe 29 is a pipe 31, having valve 32, which serves for the introduction of molten sodium hydrate. This sodium hydrate, injected in a plurality of fine streams into the molten lead-sodium alloy, is reduced by the sodium to sodium oxid, with evolution of hydrogen, which rises and passes off from the electrolytic cell through pipe 33. Sodium oxid rises and floats on the surface of the cathode and remaining in a molten condition is continuously drawn off as it rises above a certain level by an inverted siphon 34, extending from the side of vessel 1 and delivering into a vessel 35, situated in an adjoining chamber in the brickwork of the furnace. To facilitate the oxidation of the sodium, a layer 60, of loose granular conducting material, is arranged at or near the surface of the cathode around the anode-chamber. This material may consist of small angular fragments of iron, magnetite, or ferrosilicon. The material should be, at least in part, beneath the surface of the cathode, and this arrangement may be efiected either by employing a floating layer of such depth that its weight causes the lower particles to be submerged or by fixing a horizontal ring of wire-gauze between the anode-chamber 13 and the outer wall of the vessel at or below the surface of the cathode. This loose granular material serves to distribute the streams of sodium hydrate rising from pipe 29 and bring them into thorough and intimate contact with the so dium in the alloy. The oxidizing reaction is facilitated by the innumerable local couples dueto the contact of the sodium and the relatively negative particles of iron, &c. The sharp corners of the particles also increase the speed of the reaction.

The oxidation of the sodium may also be effected by successively introducing oxygen and hydrogen or air and natural gas through pipe 29, the oxygen serving to convert the which is then reduced to metallic lead by the hydrogen, with production of sodium'hydrate.

The sodium oxid received in vessel 35 is maintained in a molten condition by any suitable means, as by the waste products escaping from the main furnace-chamber through a side passage 36, sweeping around the vessel and passing out through openings 37 in the supporting-flange of the vessel. Vessel 35 has a cover 39, through which passes the stem of a float level-indicator 40. The sodium oxid may be withdrawn, if desired, through valved outlet 38. It ispreferred, however, to continuously convert this oxid into hydrate. For this purpose a pipe 41 leads upward from beneath the level of the molten oxid in vessel 35 past a steam-injector 42, which serves both to introduce the water necessary for hydration and to carry the old material upward to a vessel 43. The upper end of pipe 41 is bent and extends downward into vessel 43 to open beneath the surface of the molten sodium hydrate therein. A springclosed air-inlet valve is arranged in the bend to prevent any siphoning of hydrate back through pipe 41. Vessel 43 is heated by a burner 45 and has a valved outlet 46 for the finished product. The cover of vessel 43 also carries a level-indicator 47. Such amount of sodium hydrate as is required to oxidize the sodium taken up by the lead cathode continuously passes off from vessel 43 through a trapped outlet 48,communicating with pipe 31.

The modification shown in Fig. 2 is similar in most respects to the apparatus already described, with the exception that a mercury cathode is employed, while the electrolyte is an aqueous solution, no external heat being therefore required. The anode-chamber 14 is preferably constructed of glass or porcelain without lining. The oxidation of the sodium taken up by the cathode 23 may be effected in the usual manner by placing a layer of water 49 on the surface of the cathode around the anode-chamber, into which depend carbon electrodes 50, short-circuited to the oathode' by connections 51 to the metallic cover of the metal-containing vessel. e prefer ably employ, however, for this purpose a perforated-annulus of pipe 29, like that heretofore described, by which water or a dilute solution of sodium hydrate is injected into the body of the mercury-sodium amalgam, the resulting strong sodium-hydrate solution being withdrawn through side outlet 34. The resulting solution may be further strengthened by recirculating it through the amalgam with or without previous additions of water. The floating diaphragm 22 employed in this modification may be of broken magnetite, as heretofore, or of broken glass or silica sand. A layer 60 of conducting particles on and beneath the surface of the cathode around the anode-chamber may be employed to facilitate'oxidationof the sodium, as heretofore described. hen sodium or other easily-oxidizable metal is deposited into the mercury, the resulting amalgam being lighter than the mercury rises around the anodechamber to alevel where the sodium is oxidizcd and removed,the depleted mercury again returning to its position beneath the diaphragm.

The term alloy as used in the claims is intended to also cover an amalgam or alloy containing mercury.

Various modifications may be made in the apparatus shown and described within the scope of the generic claims. The partition which divides the containing vessel into an electrolyzing and an oxidizing compartment may be of other form and arrangement than the tubular anode-chamber shown. The dia phragm and superposed electrolyte may be placed outside of the tubular partition and the oxidizing agent introduced Within it, or a straight depending partition may be employed to partially separate the two chambers.

By the term depending partition as used in the claims is meant any partition which has a passage or passages at its lower portion. If the diaphragm is a rigid sheet, both it and the partition may be arranged in an inclined position.

In some cases the diaphragm maybe entirely omitted if care is taken to maintain the bodies of electrolyte, liquid metal, and products of oxidation at uniform levels.

The height of the column of electrolyte required to counterbalance the liquid metal cathode outside the anode-chamber may be d ecreased by slightly increasing the normal atmosphericpressure on the surface of the electrolyte. This may be easily effected by re stricting the outflow of chlorin by regulating valve or choking device 27 in the outlet-pipe 27 and dispensing with the injector 28. The weight of this column resting on the cathode is advantageous in that it serves to bring the electrolyte and liquid metal into close contact.

The arrangement shown in Fig. 3 is similar to those already described, with the exception that the electrolyzing-current is passed in a reverse direction that is, from the liquid metal -through the electrolyte. In this figure 52 represents a vessel having a partition 53, both of non-cond uctive material, and a horizontal diaphragm 54. The body 55 of molten lead extends beneath the diaphragm and to a higher level at one side of the partition. Electrolyte 56, fused. sodium chlorid, floats upon the lead and contains the cathode 59. Upon the other surface of the molten lead is a body of moltenlead chlorid 57, communicating with which is the anode 58. The electrolytic current decomposes the sodium chlorid, liberating the sodium, which maybe skimmed. off or, if the temperature is su'liiciently high, removed as a vapor. The chlorin combines with the lead, and

the lead chlorid flows up into the body of lead chlorid, which is simultaneously electrolyzed,

- liberating chlorin and returning the lead to receive further addition of chlorin. By depressing the anode 58 into the lead lead may be continuously produced and drawn ofl, further additions of metallic lead being then required.

Having now described my invention, what I claim as new, and desire to secure by Letters Patent, is

1. An apparatus for electrolyzing lightmetal compounds comprising a containing vessel, a partition including a diaphragm, dividing the vessel into two compartments, an anode in one compartment, amolten-metal cathode in the other compartment and in contact with the diaphragm, the upper surface of the cathode being above its surface of contact with the diaphragm, means for removing the light metal from the alloy or amalgam produced by electrolysis as it rises to the upper surface of the cathode, while the depleted portions of the cathode return into contact with the diaphragm, thereby effecting an automatic circulation of the cathode between the points where it receives and gives up the light metal, and means for maintaining the electrolyte in a mo]- ten condition, as set forth.

2. An apparatus for electrolyzing lightmetal compounds comprising a containing ve. scl, a partition including a diaphragm of loose granular material, dividing the vessel into two compartments, an anode in one compartment, a liquid-metal cathode in the other compartment and supporting the diaphragm the upper surface of the cathode being above its surface of contact with the diaphragm, and means for removing the light metal from the alley or amalgam produced by electrolysis as it rises to the upper surface of the cathode, while the depleted portions of the cathode return to contact with the diaphragm, thereby effecting an automatic circulation of the cathode between the points where it receives and gives up the light metal, as set forth.

An apparatus for removing an easily-oxidizable metal from a liquid alloy, comprising means for injecting an oxidizing reagent beneath the surface of the alloy and a layer of granular material in position to distribute the reagent throughout the body of the alloy, as set forth.

4. An apparatus for removing an easily-oxidizable metal from a liquid alloy, comprising means for injecting an oxidizing reagent be neath the surface of the alloy, and a layer of granular material electronegative with relation to the oxidizable metal, in position to distribute the reagent throughout the body of the alloy, as set forth.

5. As a means for removing an easily-oxidizable metal from a molten alloy which is solid at ordinary temperatures, particles of granular material electronegativc with relation to the oxidizable metal, in contact with the alloy, an oxidizing electrolyte in contact with said granular material and alloy and means for effecting an automatic circulation of the cathode between the points where it receives and gives up the light metal, as set forth.

6. An electrolytic apparatus comprising a containing vessel, a body of liquid metal therein, means for electrolytically depositing an easily-oxidizable metal upon said body while in said vessel, means for uniformly distributing an oxidizing reagent throughout a portion of the resulting alloy and means for effecting an automatic circulation of the cathode between the points where it receives and gives up the light metal, as set forth.

7. An apparatus for removing an alkali metal from a liquid alloy, comprising means for injecting sodium hydrate into the alloy, means for removing the resulting product, and means for introducing water into this product and again returning it into contact with the alloy, as set forth.

8. An electrolytic apparatus, comprising a receptacle divided into compartments communicating at the lower part thereof by a passage or passages, a liquid cathode in the lower part of the receptacle and extending above the communicating passage thereby separating the receptacle into independent chambers, an anode, an anode-chamber containing a liquid electrolyte above the liquid cathode and means, supplemental to the weight of the electrolyte, for maintaining the level of the cathode underneath the electrolyte in the anode-chamber, below its level in the opposite compartment. 9. An electrolytic apparatus, comprising a receptacle, a liquid-metal cathode, an anode, an anode-chamber having its lower end in contact with the cathode, a body of electrolyte within the anode-chamber, an oxidizing-chamber having its lower end in contact with the cathode, and means, supplemental to the weight of the electrolyte, for maintaining the level of the cathode underneath the electrolyte below its level in the oxidizing-chamber. v 10. An electrolytic apparatus, oomprisinga receptacle divided by a partition into compartments communicating at the lower part thereof, a liquid cathode in the lower part of" said receptacle separating it into independent chambers by contact with the lower edge of the partition, an anode, an electrolyte in the anode-chamber above the cathode, means for oxidizing the electrolytic contents of the oathode inthe separate or oxidizing chamber,an fl means, supplemental to the weight of the electrolyte, for maintaining the level of the cathode underneath the electrolyte below its level in the oxidizing-chamber.

In testimony whereof I have signed my name to this specificationin the presence of two subscribing witnesses.

HENRY SPENCER BLACKMORE.

l/Vitnesses:

FRANK H. HoY'r, J. R. FRITH, Jr. 

